Insulated conductor



Jan. 13. 1925.

H. W. TURNER INSULATED CONDUCTOR Filed March 2, 1925 Inventor- HarryWTUrner;

9 His flttorneg Patented Jan. 13, 1925.

HARRY W. TURNER, OF SCHENRCTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRH COMPANY, A CORPORATION OF NEW YO INSULATED CONDUCTOR.

Application filed March 2, 1923. Serial No. 622,236.

To all whom it may concern:

Be it known that I, HARRY W. TURNER, a citizen of the United States, residing at Schenectady, in the county of Schenectady,

E State of New York, have invented certain new and useful Improvements in Insulated Conductors, of which thefollowing is a specification My, invention relates to insulated electri- 10 cal conductors and has for its object the provision of a method and means for compacting and tightening the insulating material on the conductor, and for forming the conductor to a uniform size.

In accordance with one method of insulating electrical conductors, the conductor is wrapped with a suitable fibrous material, such as multiple strand cotton, which is drawn as tightly as possible. The covering is then impregnated or treated with a suitable insulating material, for example, as described and claimed in my copending application, Serial No. 449943, filed March 5, 1921. My invention has particular application to conductors provided with the multiple strand, treated cotton covering, although it obviously has application to con.- ductors provided with various other forms of fibrous insulating coverings. Where the conductor-is circular in cross section the covering is obviously held with an equal tension against the conductor throughout its periphery. In case the conductor has a prismatic cross section, however, such as rectangular, the threads or strands are pulled against the conductor with a greater tension at the corners than, along the sides. In fact, there is practically no tension between the corners tending to pull the threads against the conductor. For this reason, the threads have a tendency to be loose on the conductor between the corners whereby a greater space is taken up than is necessary.

In accordance with my present invention I pass the conductor through a heated die whereby the insulating covering is tightened and compacted into the smallest possible space.

For a betterunderstanding of my invention reference should be had to the accompanying drawing in which Fig. 1 shows in somewhat diagrammatic form apparatus for compacting the insulating materlal on electric conductors ingaccordance with my invention; while Fig. 2 is a perspective view of a die through which the conductor is drawn, showing a conductor being pulled therethrough.

Referring to the drawing, the multiple strand cotton covered conductor 10, which has been saturated with a suitable insulating bonding compound, for example, a heated asphaltum compound, as described and claimed in my aforesaid tion, is drawn from the reel 11, passed under an idler pulley 12, and then is drawn upward through a heated die 13. This die is mounted in a suitable support 14 provided with an electric heater such as an electric heating resistance (not shown) surrounding the die by means of which the die may be maintained at a suitable temperature. Conductors 15 and 16 are provided for connecting the electric heater with a suitable source of supply (not shown). As shown the support 14 is mounted for convenience On a table 17.

The effect of the die in tightening and compacting the insulating covering is clearly shown in Fig. 2 in which a section of the conductor is shown being drawn throu h the die from the left to the right as indicated by the arrow. The temperature of the die is sufficient to soften the bonding compound so as to loosen the surface of the insulating covering 18 somewhat although it is not sutficient to loosen the covering entirely from the conductor. By observing the right hand end of the conductor it will be noted that the strands along the side of the conductor have been laterally displaced and have taken a curved form indicating that all slack has been taken up. Any unevenness in the thickness of this insulating coverin is also smoothed out. In passing throug the die the insulating covering is thus compacted into the smallest possible space and is made of uniform thickness. The overall dimensions of the conductor with its insulation are also brought true to size as determined by the size of the die so that the conductor may be fitted easily into the smallest possible space.

In compacting the insulating covering as previously described, it is important that the insulating covering should rigidly adhere to the conductor. When the cotton covering has been treated with a heated asphaltum compound in accordance with copending applicaof the covering allowing them to slip suf-.

ficiently to permit all slack being taken up.

\Vhile I have described my invention as embodied'in concrete form and as operating in a specific manner in accordance with the provisions of the patent statutes, it should be understood that I do not limit my invention thereto, since various modifications thereof will suggest themselves to those skilled in the art without departing from the spirit of my invention, the scope of which is set forth in the annexed claims.

lVhat I claim as new and desire to secure by Letters Patent of the United States, is

1. Themethodof taking up slack in a multiple strand insulating'co'vering treated with a bonding compound which consists in displacing said strands laterally.

2. The method of taking up slack in amultiple strand insulating covering treated with a bonding compound which consists in applying heat to said covering so as to loosen said ,strands and then displacing said strands laterally.

' 3.- The method of tightening and compacting a treated fibrous insulating covering wound on a conductor which consists in passing the conductor through a heated die and thereby displacing portions of the turns of sald covering laterally.

4. The method of tightening and com-" pacting a multiple strand insulating covering treated with a heated compound on a conductor of prismatic section which consists in' passing the conductor through a heated die whereby the outer strands of said covering are laterally displaced.

5. Apparatus for taking up slack in a,

fibrous treated insulating covering for electric conductors comprising a die through which the conductor is drawn, and means for heating said die whereby the outer fibers of said covering are temporarily loosened and displaced laterally as the/conductor is drawn therethrough.

In witness whereof, I have hereunto set my hand this 28th day of February, 1923.

- HARRY W. TURNER. 

